'37 Pontiac 6 Exhaust Manifold Cover

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I've searched the web and couldn't find any reproductions of a '37 Pontiac exhaust manifold cover only an exploded engine view drawing of it. The shop manual shows it as group #3602, part #497612. It appears to be just a sheet metal piece. My manifold doesn't have one so I guess I get to fabricate one myself. The drawing is only a line drawing but looks as if the edges of it are formed a bit, can't really tell from a line drawing. The base of the two screws on the manifold that hold this cover in place are raised just a bit off the surface of the manifold so I'm guessing there is an air space or gap of maybe 1/16" or so. Is that correct or do the edges of the cover plate rest against the manifold body? Sure wish I had a picture of an stock cover. Since you can't really remove one without removing the exhaust manifold first, does anyone have a picture of this cover, maybe when they overhauled their manifolds? I sure would appreciate a pix or possible able to talk to someone who made their own cover. Any help would be appreciated!

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My 1937 parts manual lists it as used on 1936-37 6cyl and 1935-37 8 cyl, part #497618, but has no drawing.

It took me a bit to figure out which cover you were talking about. That thing is basically impossible to see with the engine assembled. The cover just covers a cavity which forms a "choke stove" for the automatic choke. For that to work right,, there has to be a way for air to get in.

I found the exploded view Early Times Chapter used to have posted:

I will try to scare up a picture. I may have one. I collected scads of pics of Pontiac sixes when I was making some missing parts for my engine a couple of years ago.

Hardly anything is reproduced for Pontiac, so you will either be looking for used, NOS (ask both Kurt Kelsey and California Pontiac), or making your own.

EDIT: I see now there are holes to let the air in. Any plate that covers the cavity and has a couple of holes in it would be functional.

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Yes, I grabbed that Early Times Chapter view also when the site was up. Viewing the drawing I couldn't tell if the two holes closest together, 4.5" apart, were the anchor holes for the plate or the furthest apart holes in the corners were the screw holes? Then I noticed the two raised bumps on the exhaust manifold that are further apart, passed the screws holes, at about 14" apart so then I wondered which holes were the screw holes?

If the cover plate rests on the manifold's raised area around the screw holes I would guess the plate has a gap between it and the manifold. So with a gap, why would you need holes in the plate for air to pass into the cavity? Doesn't seem necessary to me or maybe the original plate sat against the manifold. Is your cover plate up against the manifold body?

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Here's some pictures of the shield you are looking at. This is on an 8 cyl manifold. The 2 holes help to heat the air faster by forcing it to follow the manifold before entering the cavity in the casting and then up the stove pipe and then to the choke spring and then into the carb... Hope that makes sense. If you make your own stove pipe/hot air tube, just make sure it does not reach the bottom of the cavity. In theory, it could suck rust chips into the carb since this air is unfiltered... Highly unlikely though, as such a small amount of air is moving through... John

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Reread your post... The plate does fit tight to manifold all around.. as mentioned to force air against manifold. My pic may show a gap, but that's cause I stuck a putty knife in behind it to free up some rust.... John

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The last one is my car (1936 Master 6), and shows why it is nearly impossible to get a look at this thing. That green bit is the head. I thought I had a picture of the cavity underneath, but couldn't find it. All the plate has to do is let a little fresh air in that will be heated in the cavity, and then sucked up into the choke housing through that little piece of flex tubing.

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Oh boy, thanks a bunch guys, those pix are better than I thought I'd ever get to see! It's exactly what I needed since I want to keep as close to the original look as I can. I'm an old, retired, shop teacher, emphasis on the 'old', so fabricating a copy shouldn't be too hard. I blocked all the holes in the manifolds, sand blasted both and painted them with high temp manifold paint. But I couldn't put them back on the car until I figured out what to do with this cover plate I didn't have.

I original thought, from the drawing, that the furthest cover dimples or holes maybe rested on the further away bumps (about 14" apart) but now I can see, thanks John for the tape measure pix, how large the plate is and now figure those bumps are most likely remanent sprue holes from when they poured the cast iron to guarantee a full, complete casting.

I do have another question. My grandfather's car didn't have a 3.326 deflector either but it did have two carb. gaskets in place. Guess I'll have to make another piece. I would assume the deflector went between the gaskets. Is that correct? Also is the bend in that plate at 90 degrees? I've views some web pix of that deflector, from the right side of the engine, that show the vertical part to be equally spaced on the left and right side of the carb. But in the above exploded diagram it appears to be made to mostly extend to the front of the engine? I don't think it's the viewing angle because of the oblique, exploded drawing or the different looking horizontal part on the right side of the carb hole. Which is the correct position for this deflector? Would you have any idea of the metal gauge of this piece? Any measurements of the vertical part, length and width?

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I believe the exploded view is from a 1941 parts manual. I have not seen that shield on a 1937. My 1937 parts manual only lists 3.326 for 1930-32.

That shield does exist on newer flathead Pontiacs. I believe a shield like that for a Carter W-1 or WA-1 one-barrel would be asymmetrical, sticking forward under the fuel bowl. For a carb with the bowl tucked in closer, like the 2-barrels used on the last flathead Pontiacs, the shield would be more square.

Some guy on Ebay reproduces them for Hudsons. They look like they would fit.

EDIT: I don't see them on there anymore, but there is a 2 barrel one listed. I believe it is the same seller.

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Ok, thanks for the heads-up. I'm at the public library now but I'll check into my '37 parts manual as well when I get home. My '37 touring sedan 6 has a 1949-52 single barrel carb on it so I'm not sure how that compares to a '37's original WA-1 but that's something else I'll have to look into. My carb is off the car right now waiting for a new gasket/parts kit job but I noticed it did have two carb gaskets under it. There are two carb to manifold gaskets in the carb kit. I've read somewhere that two were used to help reduce heat from the manifold. Is that why they supply two carb. gaskets in the kits?

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Good pix Bloo, thanks. Gives me a good idea of the correct position. Looks like the deflector is positioned more forward to shield more of the float bowl on most of those pix. That corresponds to how the exploded diagram deflector is drawn too.

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Well, I"m still in the need of a cover so I can put my manifolds back on the car. I contacted Kurt and he doesn't have a choke stove cover and stated he's never seen one either. So I called Joe Curtis in NC who also has parts and found out he passed away 2 years ago. I check Ebay fairly often but nothing. So now I'm wondering who else I could contact. I''m running out of ideas. Any help would be appreciated.

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Are you in Early Times Chapter or Oakland Pontiac Worldwide? I am currently in both, and get magazines. If you don't already have those to look through, post back and I will dig through mine later and see if I can find any numbers to call.

It looks like basically any flathead Pontiac would work. My pics are of 1936 6 cyl, some of the other pics in this thread are 8 cyl and much newer than 36. I do not have appropriate parts manuals to verify, but I think ALL of these are the same from 36 to the end (and maybe even back further that that). Anyone who parted out an engine might have one.

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Great Bloo, I'd be grateful if you'd do that! I have the CPA catalog but it's a no go there too. I'm not a Early Times Chapter or Oakland Pontiac member either so I'd appreciate if you'd take the time to look! I think you're correct in that Pontiac used this same choke stove cover for many years.